It’s a universally acknowledged truth that every air traveler in economy class on a long flight is in dire need of leg room. No matter how hard you try to get comfortable — slapping on a travel-friendly beauty mask, taking full advantage of the complimentary alcohol — all you really want to do is stretch out. And there’s another downside to the cramped conditions: Sitting still in those tiny AF seats can decrease your circulation and increase your risk of deep vein thrombosis (DVT). Luckily, there’s plenty you can do to keep the blood flowing, without even putting down your free Prosecco.

Woman on airplane

What is DVT?

When a blood clot forms in a deep vein — usually in a leg — it’s called DVT. If symptoms occur, and they may not, they’re typically in the calf or the thigh and may include swelling, aches or pains, and skin that’s red and/or warm to the touch. DVT can resolve on its own, but it can also lead to more serious problems.

If a piece of the clot breaks off and travels to the lungs, the resulting blockage is called a pulmonary embolism (PE). That’s some serious Grey’s Anatomy sh*t, with symptoms including dizziness, shortness of breath, chest pain, and a rapid heart rate. Note that those are also symptoms of anxiety, so if you’ve started experiencing any of those things while *worrying* about DVT, it might be time to take a Headspace break. (We’ve all been there.)

Since both DVT and PE are pretty serious, it’s important to get checked out right away if these symptoms appear in the days or weeks after a long flight. And yes, that’s one more reason to spring for travel insurance — better safe than sorry, right?

Why does it happen on planes?

Long-haul air travel is a perfect storm for DVT risk factors. First of all, you’re sitting with your knees bent. There’s an important deep vein behind your knee, and when you sit, you can compress it, thereby restricting blood flow from the calf. That restricted flow can lead to clots forming.

Second, there’s the leg room issue. You’ve got your bag under the seat in front of you, your tray table is out so you can binge Netflix originals on your tablet, and you’re doing your best not to bug the person next to you. Basically, you couldn’t move if you wanted to. That can also affect your circulation, especially when you’re stuck in one position for a long time.

Finally, there may be a few airplane-specific conditions at play. Traditionally, low oxygen levels and dry air have been thought to increase the risk of DVT, although recent research suggests otherwise. Those conditions might contribute to dehydration, which can increase blood viscosity. So skimping on water in favor of the free wine doesn’t help either.

The birth control connection

Before you freak out, know that the overall risk of travel-related DVT is low. But individual circumstances can increase someone’s personal risk. For example, height can be a factor, with taller travelers struggling more with leg room, and shorter folks being at greater risk of compression behind the knee. Certain medical conditions can also up your risk, and if you’ve had a previous clot — well, you’re probably a Serena Williams-level pro, so you already know the drill.

Hormones are also a factor. Pregnancy, recent pregnancy, and estrogen-containing medications like oral contraceptives and hormone replacement therapy can all increase the risk of DVT. But Dr. Nicole Williams, founder of the Gynecology Institute of Chicago, offers a reassuring statistic: “According to epidemiologic research, for every 100,000 women [on oral contraceptives], only about 5–10 will get a DVT.”

Dr. Williams explains that different birth control pills come with different levels of risk. “If you are on a pill that has the primary progestin component of a second or third generation such as drospirenone, the risk is actually somewhat increased, although still considered low enough to be safe.”

If you have any concerns about your pill, Dr. Williams advises speaking to your doctor before you get on a plane. And hey — if you’re still smoking, there’s no time like the present to quit. Smokers on the pill have a higher risk of DVT, especially after age 35.

How to reduce the risk

If you do fall into a higher-risk category — for example, if you’re taking birth control — there are a few easy things you can do to prepare for your next long-haul flight.

First, you can invest in compression garments. “Compression is proven to improve blood circulation, which in turn may help reduce the risk of blood pooling and deep vein thrombosis (DVT) for long-haul air travel,” says Shona Halson, senior recovery physiologist at the Australian Institute of Sport [AIS].

“To maximize benefit, it’s recommended passengers choose graduated compression garments such as 2XU compression socks or tights,” says Halson. (The AIS is a 2XU partner, so Halson’s recommendation is based on AIS research — but TBH, we’d snag these leggings just for the cute designs.)

Beyond compression gear, you can memorize a few easy in-seat exercises to keep the blood flowing in your legs. Obviously, it’s even more beneficial to stand up and walk around every 90 minutes or so — but if you’re tired or trapped in your seat, give these a try.

1. Ankle Rotations: You can exercise one leg at a time or both at once. Lift your foot and rotate it clockwise, so your big toe draws a small circle in the air. After 15 seconds, reverse the direction so your toe is drawing counterclockwise circles.

2. Heel Raises: Sitting on the edge of your seat, plant your toes against the floor and lift your heels off the ground as high as you can. Hold for a count of three. Repeat 15 times.

3. Knee-Ups: Engage your core and sit up straight with your feet flat on the floor. Maintaining a slight bend in your leg, draw one knee upwards, as high as you comfortably can. Hold for a few seconds (or do a few ankle rotations), then return to the starting position.

Do you have a fave in-flight exercise? Tell us about it @BritandCo!

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(Photo via Getty)